Cornea is a transparent avascular tissue having a diameter of about 1 cm and a thickness of about 1 mm, while conjunctiva is a mucosal membrane covering the eyeball surface posterior to the corneal margin, and the back face of the eyelid. The cornea and the conjunctiva are known to significantly affect the visual function. Keratoconjunctival disorders caused due to a variety of diseases such as corneal ulcer, keratitis, conjunctivitis and dry eye may adversely affect normal construction of epithelium, and furthermore, may impair structures and functions of the corneal stroma and endothelium, when the repair of these disorders is retarded, alternatively when these disorders are prolonged without making repair on some grounds. That is because the cornea and the conjunctiva are connected tissues. In these years, with the development of cell biology, factors participating in cell proliferation, migration, adhesion, extension, differentiation and the like had been elucidated, and it was reported that these factors play important roles in repair of corneal disorders (Japanese Review of Clinical Ophthalmology, 46, 738-743 (1992), Ophthalmic Surgery, 5, 719-727 (1992)).
On the other hand, Proc. Natl. Acad. Sci. USA, 100 (13), 7919-7924 (2003) describes that 2-phenyl-1,2-benzisoselenazol-3(2H)-one (generic name: ebselen, hereinafter referred to as “ebselen”) has an antioxidant activity, and JP-A-2001-261555 describes that ebselen is effective as a therapeutic agent for cerebral arteriosclerosis and chronic cerebral circulatory failure.
However, there is no report of study on a pharmacological effect of such a compound on an eye disease such as a keratoconjunctival disorder.